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iPhone 7 cannot connect to cellular. I have had it to my carrier and we determined it was a hardware issue. I replaced the left upper antenna and it worked great for the last five days and then returned to the, “Cellular Connection Failure,” fault. Is this an inherent issue with the iPhone 7 or am I doing something to foul up the antenna? Thanks for any feedback!
The iPhone 7 and 7+ are plagued with both Audio IC and baseband issues, in your case it’s baseband where the baseband CPU begins to separate from the board. The reason why replacing the antenna worked for a little bit was because you flexed the board just enough to get the CPU to make contact with the board. This is a repair that must be handled by a specialist that does microsoldering and is not something you should DIY as it requires skill and thousands of dollars in tools to do right. iPad Rehab and STS Telecom are good choices when it comes to board repair.
